The present invention concerns a printer especially adapted for use in recording information on a suitable recording medium through the selective application of impulses of fluid.
Pin printers are available which use solenoids to drive pins into a recording medium to form visible indicia on, for example, pressure sensitive paper. These printers, however, are only able to operate a small number of solenoids (e.g., seven) at a time because the size and weight of the solenoids make it impractical for more to be carried on the printing carriage that moves from side to side of the recording medium as printing takes place.
A similar problem is found in a non-impact printer described in U.S. Pat. No. 1,770,493 that records electrical signals by using such signals to control the application of heat to heat sensitive paper. The printing is effected by control of cold air, which emanates from the nozzle, and crosses the path of a continuous stream of hot air emanating from a second nozzle located nearby. While this unit can be moved from side to side across a recording medium, it is difficult to form an alphanumeric dot matrix using a plurality of pairs of such nozzles because a cold air nozzle must be situated adjacent each hot air nozzle. If such an arrangement could be mounted at all on a printing carriage, more than likely the horizontal and vertical size of a character printed by such a system would be much larger than that formed by, for example, a conventional typewriter. These and other disadvantages tend to foreclose any meaningful use of such a system as a compact, high speed printer which may be used like a typewriter.